With digitalized trend, many consumable electronic products are developed to integrate high-quality digital signals into diverse apparatuses. With increasing development of microelectronic technologies, the functions of the consumable electronic products are diverse and the sizes of the consumable electronic products are minimized. In addition, these consumable electronic products become essential because they are portable and convenient.
Nowadays, since the consumable electronic products such as digital still cameras and personal digital assistants (PDAs) are popular, memory cards are more important. Generally, the memory cards are employed to store data files such as the image captured from the digital still camera or the data files stored in the personal digital assistant.
The common standard specifications of memory cards comprise for example Compact Flash cards (CF cards), Secure Digital cards (SD cards), Multi-Media cards (MMC cards), Memory Stick cards (MS cards), and so on. Since the CF card has the largest volume and area among these memory cards and a high market share, the CF card is widely used in the consumable electronic products. In contrast, since the SD card, the MMC card, the XD card and the MS card have smaller volumes and areas, these cards are classified as small-sized memory cards.
Referring to FIG. 1, a schematic circuit configuration of a conventional CF card is shown. The CF card 10 comprises a CF interface connector 11, a control unit 12 and a flash memory 13. Via the CF interface connector 11, the CF card 10 can be in communication with an external electronic device (not shown) compatible with the CF interface. By the control unit 12, data are read or stored from/into the flash memory 13.
As known, specified memory cards are compatible with specified digital still cameras or personal digital assistants. If the memory card is incompatible with the electronic product, the problem of wasting resources occurs. For example, if a user has originally a personal digital assistant compatible with the CF card and wants to buy another personal digital assistant compatible with the MMC card, it is necessary to buy the MMC card because the original CF card fails to be used in the new personal digital assistant.
In view of the above-described disadvantages resulted from the prior art and the advantages of the conventional CF card, the applicant has diligently developed a composite CF card according to the present invention through wholehearted experience and research.